Automatic splaying picker finger

ABSTRACT

A cartridge picker for selectively engaging and disengaging a cartridge may comprise a thumb assembly mounted to the cartridge picker so that the thumb assembly is moveable along a first displacement path between an extended position and a retracted position. An automatically splaying picker finger having an engagement end and a mounting end is mounted to the thumb assembly at the mounting end and is moveable between a retracted position and a splayed position, so that the finger moves into the splayed position when the engagement end is moved against a cartridge. A cartridge picker positioning system is operatively associated with the cartridge picker to move the cartridge picker between a first position and a second position along a second displacement path that is substantially perpendicular to the first displacement path. The finger disengages the cartridge when the thumb assembly is in the extended position and the cartridge picker is moved to the second position.

FIELD OF INVENTION

This invention relates generally to data storage systems for handlingand storing data cartridges, such as optical disk or magnetic tapecartridges, and more specifically to cartridge access devices forengaging and retrieving the data cartridges stored in data storagesystems.

BACKGROUND

Many different types of data storage systems exist and are being used tostore data cartridges at known locations and to retrieve desired datacartridges so that data may be written to or read from the datacartridges. Such data storage systems are often referred to as “jukebox” data storage systems, particularly if they can accommodate a largenumber of individual data cartridges.

A typical juke box data storage system may include one or more differenttypes of cartridge receiving devices for holding the various datacartridges. For example, one type of cartridge receiving device maycomprise a cartridge storage rack or “magazine” while another type ofcartridge receiving device may comprise a cartridge read/write device.The cartridge storage racks or magazines serve to provide storagelocations for the data cartridges and are often arranged so that theyform one or more vertical stacks, although other configurations arepossible. The cartridge read/write device may be located at anyconvenient location within the data storage system.

The data storage system may also be provided with a moveable cartridgepicker assembly or simply “picker” for transporting the data cartridgesbetween the various cartridge receiving devices, e.g., between thecartridge storage racks and the cartridge read/write devices. A typicalpicker may also be provided with a cartridge plunge mechanism or “thumb”assembly for engaging the various data cartridges contained in thecartridge receiving devices and for drawing them into the picker. Apicker positioning system associated with the cartridge picker assemblymay be used to move the cartridge picker assembly along the variouscartridge receiving devices.

Data storage systems of the type described above are usually connectedto a host computer system which may be used to access or store data onthe data cartridges. For example, if the host computer system issues arequest for data contained on a particular data cartridge, a controlsystem associated with the data storage system will actuate the pickerpositioning system to move the picker assembly along the cartridgestorage racks until the picker assembly is positioned adjacent thedesired data cartridge. The cartridge plunge mechanism or “thumb”assembly associated with the picker assembly may then remove the datacartridge from the cartridge storage rack and draw it into the pickerassembly. The picker positioning system may then be actuated to move thepicker assembly to the appropriate cartridge read/write device. Onceproperly positioned adjacent the cartridge read/write device, the thumbassembly may insert the selected data cartridge into the cartridgeread/write device so that the host computer may thereafter read datafrom or write data to the data cartridge. After the read/write operationis complete, the thumb assembly may be actuated to remove the datacartridge from the cartridge read/write device. The picker assembly maythereafter return the data cartridge to the appropriate location in thecartridge storage rack.

A typical cartridge plunge mechanism or “thumb” assembly is usuallyslidably mounted to the picker and is provided with a thumb actuatorsystem to move the thumb assembly toward and away from a cartridgeaccess end of the picker. For example, if it is desired to retrieve adata cartridge from a cartridge receiving device, the thumb actuatorsystem moves the thumb assembly toward the cartridge access end of thepicker so that the thumb assembly can engage or “grab” the datacartridge. Thereafter, the thumb actuator system may retract the thumbassembly and engaged data cartridge into the picker. If it is desired toload the data cartridge into the cartridge receiving device, then thethumb actuator moves the thumb assembly and data cartridge toward thecartridge access end of the picker, and inserts the data cartridge intothe cartridge receiving device.

The thumb assembly may utilize any of a wide variety of devices to allowthe thumb assembly to transfer the cartridge between the cartridgepicker assembly and a cartridge receiving device. For example, one typeof cartridge engaging device comprises a plurality of jaw members whichgrip the sides of a cartridge. In this system, the jaws maintain theirhold on a cartridge using friction. In order to reliably grip acartridge, the jaws must be made of a material having a high coefficientof friction with the data cartridge. This requirement may necessitatethe use of relatively expensive materials for the jaws or the use ofmultiple materials such as a rigid plastic core and a rubber coating.The jaws also tend to be bulky due to the strength requirements in afriction system. This results in relatively large gaps betweencartridges to allow the jaws to reach in between adjacent cartridges.Furthermore, the jaws must clamp firmly around the data cartridge,requiring a bulky actuator system.

Another type of cartridge engaging device may comprise a latch member of“finger” having a hooked end to engage in a notch in the side of a datacartridge. Currently known finger systems require the use of a track onthe inside of the picker frame to cause the finger to splay down belowthe side of a data cartridge as the thumb and finger assemblies aremoved toward the cartridge.

Once the finger has moved past the face of the cartridge and cleared theedge, the track allows the finger to move up toward the side of thecartridge under the tension of a spring. When the hooked end of thefinger moves over the notch in the side of the cartridge, the springpulls the hooked end of the finger up into the notch, allowing the thumbassembly to thereafter retract and pull the cartridge into the picker.In order to insert the cartridge into a cartridge receiving device, thethumb assembly pushes the cartridge, with the finger still engaged, intothe device. A gate on the inside of the picker frame then causes thefinger to splay away from the cartridge, disengaging the hooked end ofthe finger from the notch in the side of the cartridge, before the thumbassembly and finger can retract and leave the cartridge in the device.

Finger assemblies of the type described above have several advantagesover friction jaws, such as needing only one finger rather than multiplejaws. The finger may also be made of inexpensive plastic, as thestrength and coefficient of friction requirements are much lower. Afinger assembly is also less prone to inadvertently disengage from thecartridge, as the positive engagement of the hooked end in the notch ismore secure than a friction grip on the sides of a cartridge.

However, the track and gate system that is required to move the fingeraway from the cartridge adds complexity to the picker frame. Theadditional parts required add to the size and cost of the picker andlower reliability. Furthermore, if the gate malfunctions and the fingerdisengages from the cartridge, error recovery can be difficult if thecartridge is dropped before it is correctly placed in a cartridgereceiving device.

Consequently, a need exists for an improved finger assembly to engage adata cartridge. In particular, a need exists for a finger assembly whichcan more easily be splayed away from the data cartridge using fewer andless expensive components.

SUMMARY OF THE INVENTION

A cartridge picker for selectively engaging and disengaging a cartridgemay comprise a thumb assembly mounted to said cartridge picker so thatsaid thumb assembly is moveable along a first displacement path betweenan extended position and a retracted position. An automatically splayingpicker finger having an engagement end and a mounting end is mounted tothe thumb assembly at the mounting end and is moveable between aretracted position and a splayed position, so that said finger movesinto the splayed position when the engagement end is moved against acartridge. A cartridge picker positioning system is operativelyassociated with the cartridge picker to move the cartridge pickerbetween a first position and a second position along a seconddisplacement path that is substantially perpendicular to the firstdisplacement path. The finger disengages the cartridge when the thumbassembly is in the extended position and the cartridge picker is movedto the second position.

Also disclosed is a cartridge picker for selectively engaging anddisengaging a cartridge which may comprise a thumb assembly mounted tosaid cartridge picker so that said thumb assembly is moveable along ahorizontal displacement path between an extended position and aretracted position. An automatically splaying picker finger having anengagement end and a mounting end is mounted to the thumb assembly atthe mounting end and is moveable between a retracted position and asplayed position, so that said finger moves into the splayed positionwhen the engagement end is moved against a cartridge. A cartridge pickerpositioning system is operatively associated with the cartridge pickerto move the cartridge picker between a first position and a secondposition along a vertical displacement path that is substantiallyperpendicular to the horizontal displacement path. The finger disengagesthe cartridge when the thumb assembly is in the extended position andthe cartridge picker is moved to the second position.

A method for engaging a data cartridge with a cartridge picker is alsodisclosed. A cartridge picker is provided comprising a thumb assemblymoveable along a displacement path between an extended position and aretracted position and a finger mounted to the thumb assembly so thatthe finger may be moved between a retracted position and a splayedposition. The cartridge picker is positioned adjacent the datacartridge, and the thumb assembly is moved along the displacement pathtoward the cartridge until the finger contacts the data cartridge andbegins moving to the splayed position. The movement of the thumbassembly is continued along the displacement path toward the cartridgeuntil the finger engages the notch.

A method for disengaging a cartridge picker from a data cartridge maycomprise providing a cartridge picker having a thumb assembly moveablealong a first displacement path between an extended position and aretracted position and a finger mounted to the thumb assembly so thatthe finger may be moved between a retracted position and a splayedposition. The cartridge picker is moveable along a second displacementpath that is substantially perpendicular to the first displacement path.The finger is initially engaged in a notch in the data cartridge. Thethumb assembly is moved along the first displacement path to theextended position, and the cartridge picker is moved along the seconddisplacement path until the finger is free of the notch in the datacartridge.

A method for disengaging a cartridge picker from a data cartridge in acartridge receiving device may comprise providing a cartridge pickerhaving a thumb assembly moveable along a displacement path between anextended position and a retracted position. The cartridge picker alsoincludes a finger mounted to the thumb assembly so that the finger maybe moved between a retracted position and a splayed position. Thecartridge receiving device includes a bezel. The cartridge picker ismoved adjacent the cartridge receiving device, and the thumb assembly ismoved along the displacement path toward the extended position until thefinger contacts the bezel and begins moving to the splayed position. Themovement of the thumb assembly along the displacement path is continueduntil the cartridge is inserted in the cartridge receiving device. Thethumb assembly may then be moved back along the displacement path towardthe retracted position.

BRIEF DESCRIPTION OF THE DRAWING

Illustrative and presently preferred embodiments of the invention areshown in the accompanying drawing in which:

FIG. 1 is a plan view of a media access device and cartridge pickerassembly as it may be used in a data storage system to access andtransport data cartridges contained within the data storage system;

FIG. 2 is a perspective view of a thumb assembly having an automaticallysplaying finger assembly according to the present invention;

FIG. 3 is a side view of the thumb and finger assemblies of FIG. 3;

FIG. 4 is a perspective view of the cartridge picker assembly;

FIG. 5 is a perspective view of the left side of the cartridge pickerassembly showing the thumb and finger assemblies;

FIG. 6 is a perspective view of the right side of the cartridge pickerassembly showing the thumb and finger assemblies;

FIGS. 7(a-f) are plan views showing a thumb and finger assembly invarious stages of engaging and disengaging a data cartridge in acartridge storage rack;

FIGS. 8(a-f) are elevation views of the thumb and finger assembly ofFIGS. 7(a-f);

FIG. 9 is a perspective view of a cartridge picker assembly having avertical lift system;

FIGS. 10(a-b) are elevation views showing a thumb and finger assembly invarious stages of engaging and disengaging a data cartridge in acartridge storage rack with a vertical lift system; and

FIGS. 11(a-d) are elevation views of a thumb and finger assembly invarious stages of engaging and disengaging a data cartridge in acartridge read/write device; and

DETAILED DESCRIPTION OF THE INVENTION

A cartridge picker assembly or “picker” 19 having an automaticallysplaying finger assembly 10 is shown in FIG. 1 as it could be used in a“juke box” data storage system 20 to transfer data cartridges 22 betweenone or more cartridge receiving devices, such as one or more cartridgestorage racks or magazines 24 and one or more cartridge read/writedevices 26.

The automatically splaying finger assembly 10 may comprise a body 12which is mounted at one end 51 to a cartridge plunge mechanism of “thumbassembly” 21. The automatically splaying finger assembly 10 furthercomprises an angled face surface 16 on the body 12 at the remote end 49opposite the thumb assembly 21. The automatically splaying fingerassembly 10 also comprises a hooked end or “tip” 14 which extends fromthe top 46 of the finger 10 near the remote end 49 and which is sized tofit within a notch 23 in a side edge 25 (FIG. 8a) of a data cartridge22. A spring 17 may be attached between the automatically splayingfinger assembly 10 and the thumb assembly 21 to pull the finger 10 intoa retracted position 40 (FIG. 8a).

The automatically splaying finger assembly 10 is mounted to a thumbassembly 21 of the picker 19 and allows the thumb assembly 21 to engageand disengage a data cartridge 22. Because the automatically splayingfinger assembly 10 is mounted to the thumb assembly 21, the thumb andfinger assemblies 21 and 10 move toward and away from the cartridge end36 of the picker 19 together. (see FIG. 5).

The automatically splaying finger assembly 10 may be moveably mounted tothe thumb assembly 21, allowing the automatically splaying fingerassembly 10 to move between a retracted position 40 (FIG. 8a) and asplayed position 42 on the thumb assembly 21 (FIG. 8d). In one preferredembodiment, the automatically splaying finger assembly 10 is pivotallymounted to the thumb assembly 21 by a pivot pin 18, allowing theautomatically splaying finger assembly 10 to rotate between theretracted position 40 and the splayed position 42. The pivot pin 18 ishigher than the contact point on the face 16 of the automaticallysplaying finger assembly 10 which first contacts a data cartridge 22.

The placement of the face 16 of the automatically splaying fingerassembly 10 below the pivot pin 18 enables the automatic splaying of thefinger 10, aided by the angled face 16 of the finger 10. As the thumbassembly 21 moves toward a surface such as a data cartridge 22, as shownin FIGS. 8b and 8 c, the angled face 16 presses against the datacartridge 22, causing the automatically splaying finger assembly 10 tomove downward into the splayed position 42 against the tension of thespring 17.

As the thumb assembly 21 continues to move toward the data cartridge 22,the tip 14 slides along the side edge 25 of the data cartridge 22 untilit moves over the notch 23. The spring 17 then pulls the automaticallysplaying finger assembly 10 into a locked position 41 (FIG. 8e) with thetip 14 engaged in the notch 23. The tip 14 provides positive engagementagainst the notch, locking into the notch until the automaticallysplaying finger assembly 10 is moved away from the data cartridge 22.

With the automatically splaying finger assembly 10 engaged with the datacartridge 22, the thumb assembly 21 may then retract the cartridge 22into the cartridge picker assembly 19, and the cartridge picker assembly19 may transport the cartridge 22 to another cartridge receiving device.

To disengage the automatically splaying finger assembly 10 from the datacartridge 22 when it is inserted into a cartridge read/write device 26,the thumb assembly 21 first pushes the cartridge 22 into the read/writedevice 26. As the thumb assembly 21 and automatically splaying fingerassembly 10 move toward the cartridge read/write device 26, the angledface 16 of the finger 10 contacts a bezel 48 on the drive housing 50(FIG. 11a).

The engagement of the angled face 16 with the bezel 48 causes theautomatically splaying finger assembly 10 to move to the splayedposition 42. The thumb assembly 21 then continues to push the datacartridge 22 into the cartridge read/write device 26 until the notch 23is fully covered by the cartridge read/write device 26, preventing thetip 14 from reentering the notch 23, as will be discussed in more detailhereinafter. The thumb assembly 21 may then be retracted, leaving thedata cartridge 22 in the cartridge read/write device 26.

To disengage the automatically splaying finger assembly 10 from the datacartridge 22 when it is inserted into a cartridge storage rack 24, thedata cartridge 22 is first fully inserted into the storage rack 24. Inone preferred embodiment, the notch 23 remains accessible when the datacartridge 22 has been fully inserted into the storage rack 24. Thecartridge picker assembly 19 is then moved with the thumb assembly 21still in the extended position until the tip 14 of the automaticallysplaying finger assembly 10 is removed from the notch 23, leaving thedata cartridge 22 in the storage rack 24, as will be discussed in moredetail hereinafter. The thumb assembly 21 may then be retracted into thecartridge picker assembly 19.

The automatically splaying finger assembly 10 offers substantialadvantages over friction engagement systems or track and gate fingerassemblies. The automatically splaying finger assembly 10 is a simple,reliable, and cost effective system for engaging data cartridges 22,eliminating the costly and error-prone actuators required by priorcartridge engagement systems. The automatically splaying finger assembly10 provides for improved operation by reducing the number of partsrequired and automating the splaying action of the finger 10. As aresult, engagement of data cartridges (e.g., 22) with the cartridgepicker assembly 19 is less error-prone, thereby improving the overallreliability of the juke-box data storage system 20. In addition, thesize and cost of the cartridge picker assembly 19 is lowered.

The automatically splaying finger assembly 10 provides a positiveengagement with a data cartridge (e.g., 22) which is much stronger thana friction hold. The automatically splaying finger assembly 10 has alower profile than friction systems which require strong jaws, thereforedata cartridges 22 may be placed more closely, reducing the size of thedata storage system 20. Another benefit is that tolerance requirementsare less restrictive than previous systems having a track and gatefinger actuating system or friction jaws. Finally, error recovery issimplified since the automatically splaying finger assembly 10 is onlysplayed away from a cartridge 22 after it is been placed in a cartridgereceiving device (e.g., 24 and 26).

Having briefly described the automatically splaying finger assembly 10,as well as some of its more significant features and advantages, thevarious embodiments of the automatically splaying finger assembly 10according to the present invention will now be described in detail.However, before proceeding with the description, it should be noted thatthe automatically splaying finger assembly 10 according to the presentinvention may be utilized in any of a wide range of cartridge engagingassemblies in any of a wide variety of data storage systems now known orthat may be developed in the future. Accordingly, the present inventionshould not be regarded as limited to the particular data storage system20 and cartridge picker assembly 19 shown and described herein.

With the foregoing considerations in mind, one embodiment of anautomatically splaying finger assembly 10 is shown and described hereinas it may be used in a cartridge picker assembly 19. The cartridgepicker assembly 19 may, in turn, be used in a portion of a “juke box”data storage system 20. In one preferred embodiment, the juke box datastorage system 20 may comprise a data storage system of the type shownand described in U.S. patent application Ser. No. 09/045,134, filed Mar.20, 1998, entitled “Multi-Plane Translating Cartridge Handling System,”which is incorporated herein by reference for all that it discloses.Alternatively, the data storage system 20 may be of the type shown anddescribed in U.S. Pat. No. 5,596,556, entitled “Linear Displacement andSupport Apparatus for use in a Cartridge Handling System,” which is alsoincorporated herein by reference for all that it discloses. The datastorage system 20 may also be of the type shown and described in U.S.patent application Ser. No. 09/137,350, filed Aug. 20, 1998, entitled“Modular Data Storage System,” which is incorporated herein by referencefor all that it discloses.

Referring now primarily to FIG. 1, the data storage system 20 shown anddescribed in U.S. patent application Ser. No. 09/045,134 referred toabove may comprise a generally rectangularly shaped frame or chassisassembly 28 having a pair of opposed side portions 52 and 54 and an endportion 56 around which are positioned various cartridge receivingdevices. More specifically, a pair of cartridge storage racks ormagazines 24 may be positioned adjacent each opposed side portion 52 and54 of the frame or chassis assembly 28, whereas a pair of cartridgeread/write devices 26 may be positioned adjacent the end portion 56 ofthe frame assembly 28. Accordingly, the various cartridge receivingdevices (e.g., the cartridge storage racks or magazines 24 and thecartridge read/write devices 26) define a generally U-shapedconfiguration.

A picker positioning system 34 may be used to move the cartridge pickerassembly 19 along the U-shaped guide track 30. For example, in theembodiment shown and described herein, the picker positioning system 34may move the cartridge picker assembly 19 between a first position 60adjacent the first side portion 54 of the frame assembly 28, a secondposition 60′ adjacent the end portion 56 of frame assembly 28, and athird position 60″ adjacent the second side portion 52 of frame assembly28.

The picker positioning system 34 may comprise a rack and pinion drivesystem having a U-shaped gear rack 62 mounted to the lower plate 64 offrame assembly 28 at a position adjacent the U-shaped guide track 30.The cartridge picker assembly 19 may be provided with a lower piniongear 66 (FIG. 4) sized and positioned so that it will engage the lowerU-shaped gear rack 62 provided on the lower plate 64. Similarly, thecartridge picker assembly 19 may also be provided with an upper piniongear 68 sized and positioned so that it will engage an upper U-shapedgear rack provided on an upper plate 70 (not shown). A drive pinionactuator system 72 mounted to the cartridge picker assembly 19 may beused to drive the lower and upper pinion gears 66 and 68, therebyallowing the picker assembly 19 to be moved along the U-shaped path 32.

The details of the cartridge picker assembly 19 that may be utilized inone preferred embodiment of the present invention are best seen in FIGS.4-6. Essentially, the cartridge picker assembly 19 may include a pickerframe assembly 76 having a first side wall or member 78 and a secondside wall or member 80. The two side members 78 and 80 define aninterior chamber or cavity 74 of sufficient size to receive a datacartridge 22. The thumb assembly 21 is slidably mounted to the frameassembly 76 so that the thumb assembly 21 may be moved along an X axistoward and away from the cartridge access end 36 of frame assembly 76,i.e., generally in the directions of arrows 38 and 39, respectively.(See FIG. 6)

The thumb assembly 21 may be mounted on first and second elongate guiderails 82 and 84 that are provided on the first and second sides 78 and80 of the picker frame assembly 76. (See FIGS. 5 and 6) The main bodyportion 86 of the thumb assembly 21 may include a first flange member 88sized and positioned to engage the first elongate guide rail 82. Themain body portion 86 of the thumb assembly 21 may also include a secondor C-shaped flange member 90 adapted to engage the second elongate guiderail 84. The thumb assembly 21 is thereby guided and supported as it ismoved in the cartridge picker assembly 19 toward and away from thecartridge access end 36.

The various components just described may be made from any of a widerange of materials, such as metals or plastics, suitable for theintended application. For example, in one preferred embodiment, thefirst and second side members 78 and 80 comprising the picker frameassembly 76 are molded from a polycarbonate plastic material.Accordingly, the various components and features contained therein,e.g., the guide rails 82 and 84 may be provided as integral componentsof the respective side members 78 and 80. Alternatively, the first andsecond side members 78 and 80 comprising the picker frame assembly 76may be made from other materials, in which case the various componentsand features of the side members 78 and 80 may comprise integralcomponents or separate elements, depending on the particular design andmaterial to be utilized.

The main body portion 86 of the thumb assembly 21 may also be made fromany of a wide range of materials suitable for the intended application.For example, in the embodiment shown and described herein, the main bodyportion 86 of thumb assembly 21 is made from nylon with a small amountof Teflon® added (e.g., about 15% by weight) as a friction modifier,although other materials could also be used.

The thumb assembly 21 may be moved toward and away from the cartridgeaccess end 36 of the cartridge picker assembly 19 by any of a wide rangeof actuator systems. By way of example, in one preferred embodiment, thethumb assembly 21 may be moved by a rack and pinion drive assembly ofthe type shown and described in U.S. patent application Ser. No.09/045,558, filed Mar. 20, 1998, and entitled “Cartridge Picker Assemblywith Rack Drive Thumb Actuator System,” which is incorporated herein byreference for all that it discloses. Alternatively, other types of thumbactuator systems may be used.

The rack and pinion drive system utilized in one preferred embodiment ofthe present invention and shown and described in U.S. patent applicationSer. No. 09/045,558, referred to above, is best seen in FIGS. 2, 4, and5 and may comprise an elongate gear rack 92 that is affixed to the firstside member 78 of the picker frame assembly 76. The main body portion 86of the thumb assembly 21 may be provided with a pinion gear 93positioned so that it engages the gear rack 92. The pinion gear 93 iscaused to rotate by a drive system 94 which, in one preferredembodiment, includes a motor 95 and a gear reduction system 96. Themotor 95 may be mounted to the main body portion 86 of the thumbassembly 21 and is operatively associated with the gear reduction system96 so that the motor 95 rotates the pinion gear 93 to extend and retractthe thumb assembly 21.

The motor 95 may comprise any of a wide range of motors suitable for theintended application. In one preferred embodiment, the motor 95comprises a permanent magnet D.C. motor, such as model no. RS-385PH,available from Mobuchi Co. of China, although other types may also beused.

The gear reduction system 96 may comprise a conventional gear reductionsystem utilizing a plurality of spur gears to provide a reduction ratiosufficient to allow the motor 95 to extend and retract the thumbassembly 21 at an appropriate speed and with sufficient force towithdraw and insert the data cartridge 22 into the selected cartridgereceiving device. In one preferred embodiment, the gear reduction system96 provides a reduction ratio of about 11.5:1, although other ratios maybe used depending on, for example, the speed and torque characteristicsof the particular motor 95 that is selected. The various spur gearscomprising the gear reduction system 96 may be made from any convenientmaterial, such as metal or plastic, suitable for the intendedapplication. By way of example, in one preferred embodiment, the variousspur gears comprising the gear reduction system 96 are made from brassand stainless steel. Alternatively, the gear reduction system couldutilize other types of gears, such as worm gears, to provide the desiredreduction.

The foregoing description of the data storage system 20 and relatedcomponents (e.g., the cartridge picker assembly 19, thumb assembly 21,and picker positioning system 34) is provided in order to betterunderstand one environment in which the automatically splaying pickerfinger 10 according to the present invention may be used. However, aswas mentioned above, it should be understood that the automaticallysplaying picker finger 10 may be used in any of a wide range of othertypes of data storage systems or other similar devices having moveableinternal components. Consequently, the present invention should not beregarded as limited to the particular data storage system 20 shown anddescribed herein.

Referring now primarily to FIGS. 2 and 3, the automatically splayingpicker finger 10 in one preferred embodiment may comprise a body 12which is moveably mounted at one end 51 to a thumb assembly 21. In onepreferred embodiment, the automatically splaying picker finger 10 may bemounted by a pivot pin 18 which enables the automatically splayingpicker finger 10 to pivot about axis 58 (FIG. 5) between a retractedposition 40 (FIG. 8a) and a splayed position 42 (FIG. 8d).Alternatively, the automatically splaying picker finger 10 may bemoveably mounted to the thumb assembly 21 in any manner which enablesthe finger 10 to move between the retracted and splayed positions 40 and42.

The automatically splaying picker finger 10 further comprises a facesurface 16 located on the body 12 at the end 49 opposite the thumbassembly 21. The body 12 is relatively longer at the bottom 44 than atthe top 46, causing the face surface 16 to be angled back at the top 46.The automatically splaying picker finger 10 also comprises a tip 14which extends from the top 46 of the finger 10 near the end 49 to engagein a notch 23 of a data cartridge 22 (FIG. 8a). The pivot pin 18 islocated above the face 16 of the automatically splaying finger assembly10 along a Z axis to facilitate the automatic splaying action.

The various elements of the automatically splaying picker finger 10 justdescribed may be made from any of a wide range of materials, such asmetals or plastics, suitable for the intended application. For example,in one preferred embodiment, the automatically splaying picker finger 10is made of stainless steel.

In a preferred embodiment, the automatically splaying picker finger 10is used to engage digital linear tape (DLT) cartridges such as modelnumber DLTtape IV, available from Quantum Co. of Milpitas, Calif. Insuch an application, the automatically splaying picker finger 10 mayhave a width 47 (FIG. 7a) between about 1 mm and about 2 mm (1.3 mmpreferred). The tip 14 may have a height 43)between about 3 mm and about4 mm (3.5 mm preferred). The tip 14 may be located a distance 45 betweenabout 17 mm and about 20 mm (18 mm preferred) from the thumb assembly 21when the automatically splaying picker finger 10 is in the lockedposition 41 (see FIG. 8e). When the automatically splaying picker finger10 is in the retracted position 40, as shown in FIG. 8a, the angle 53that face 16 makes with the data cartridge 22 may be between about 12degrees and about 20 degrees (16 degrees preferred). The verticaldistance between the pivot point 18 and the bottom 44 of the face 16 ofthe automatically splaying picker finger 10 may be between about 10 mmand about 20 mm (15 mm preferred), enabling the automatically splayingpicker finger 10 to splay when the face 16 contacts the cartridge 22.

The automatically splaying picker finger 10 is biased toward theretracted position 40 by a spring 17 which is attached between the body12 of the finger 10 and the thumb assembly 21. In a preferredembodiment, the spring 17 may comprise a metal coil spring, such as partno. E 0180-018-1370, available from Associated Spring Co. of Corry, Pa.,which provides a tension of between about 1.0 newtons (n) and about 1.5n on the automatically splaying picker finger 10. The automaticallysplaying picker finger 10 is prevented from moving beyond the retractedposition 40 under the tension of the spring 17 by the body 86 of thethumb assembly 21. Referring now primarily to FIGS. 7a-7 f and 8 a-8 f,the operation of the automatically splaying picker finger 10 whenengaging data cartridges 22 in a storage magazine 24 is as follows.

The picker 19 is first positioned along the picker positioning system 34adjacent the cartridge 22 by the drive pinion actuator system 72 asdescribed previously. The picker 19 is correctly positioned adjacent thedata cartridge 22 when the automatically splaying picker finger 10 isadjacent the notch 23 in the cartridge 22, as shown in FIG. 7a.

To engage the data cartridge, the thumb assembly is initially retractedin the picker 19 opposite the cartridge access end 36. The automaticallysplaying picker finger 10 is held against the body 86 of the thumbassembly 21 in the retracted position 40 by the spring 17. The thumbassembly 21 may then be moved inside the cartridge picker assembly 19 indirection 38 toward the data cartridge 22 by the rack and pinion drivesystem as discussed previously. The notch 23 provided in the side 25 ofthe data cartridge 22 allows the tip 14 of the automatically splayingpicker finger 10 to engage the cartridge 22 once the finger 10 has beenproperly splayed and positioned.

The thumb assembly 21 is then moved toward the data cartridge 22 untilthe face 16 of the automatically splaying picker finger 10 is in contactwith the cartridge 22. (See FIGS. 7b and 8 b) The resulting forceagainst the angled face 16 of the automatically splaying picker finger10, combined with the face 16 being placed lower than the pivot pin 18along a Z axis, causes the automatically splaying picker finger 10 topivot toward the splayed position 42. As the thumb assembly 21 movescloser to the data cartridge 22, the automatically splaying pickerfinger 10 pivots to the splayed position 42 against the tension of thespring 17, allowing the tip 14 of the finger 10 to clear the edge 25 ofthe cartridge 22. (See FIGS. 7c and 8 c).

The thumb assembly 21 then continues to move toward the data cartridge22 with the tip 14 of the automatically splaying picker finger 10sliding along the side 25 of the cartridge 22 toward the notch 23. (SeeFIGS. 7d and 8 d) The tension of the spring 17 holds the automaticallysplaying picker finger 10 in splayed position 42 against the side 25 ofthe data cartridge 22.

When the thumb assembly 21 has moved toward the data cartridge 22 untilthe tip 14 is positioned over the notch 23, the spring 17 pulls the tip14 into the notch 23. (See FIGS. 7e and 8 e) The movement of the thumbassembly 21 in direction 38 towards the cartridge access end 36 of thepicker 19 may stop once the tip 14 of the automatically splaying fingerassembly 10 is engaged in the notch 23 in the data cartridge 22 and thefinger 10 has entered the locked position 41. The body 86 of the thumbassembly 21 is in contact or is nearly in contact with the datacartridge 22. The thumb assembly 21 and data cartridge 22 may then beretracted into the cartridge picker assembly 19 to transport the datacartridge 22 to another cartridge receiving device 24 or 26.

To disengage the automatically splaying picker finger 10 from the datacartridge 22 in a magazine 24, the cartridge 22 is first fully insertedinto the magazine 24 as shown in FIGS. 7f and 8 f. The cartridge pickerassembly 19 is then moved along one of the existing degrees of freedomfound in the picker drive systems (e.g., 34). For example, in oneembodiment, the cartridge picker assembly 19 is moved laterally along aY axis (FIG. 4) by the picker positioning system 34, thereby sliding thetip 14 of the automatically splaying picker finger 10 out of the notch23. The cartridge picker assembly 19 is moved laterally along adisplacement path which is substantially perpendicular to thedisplacement path of the thumb assembly 21 inside the picker 19. Thesubstantially perpendicular relationship between the first displacementpath of the thumb assembly 21 and the second displacement path of thecartridge picker assembly 19 exists at all locations of the cartridgepicker assembly 19 along the U-shaped track 30. For example, when thecartridge picker assembly 19 is adjacent a cartridge read/write device26 (see FIGS. 1 and 9), the lateral motion of the picker 19 along thesecond displacement path is along an X axis, and the motion of the thumbassembly 21 along the first displacement path in the picker 19 is alonga Y axis. When the cartridge picker assembly 19 is adjacent a storagemagazine 24, the lateral motion of the picker 19 along the seconddisplacement path is along the Y axis, and the motion of the thumbassembly 21 along the first displacement path in the picker 19 is alongthe X axis.

In one preferred embodiment, the cartridge picker assembly 19 is movedlaterally along between about 6 mm and about 8 mm (7 mm preferred) todisengage the tip 14 from the notch 23. As the tip 14 clears the bottom27 of the data cartridge 22, the automatically splaying picker finger 10is pulled by the spring 17 into the retracted position 40. The thumbassembly 21 and the automatically splaying picker finger 10 may then bemoved into the cartridge picker assembly 19, leaving the data cartridge22 resting in the magazine 24. Any inadvertent lateral movement of thecartridge picker assembly 19 when the data cartridge 22 is onlypartially protruding from the picker assembly 19 will not disengage theautomatically splaying picker finger 10 from the cartridge 22, as thesides 78 and 80 of the picker assembly 19 will cause the cartridge 22 tomove laterally with the picker assembly 19. As a result, theautomatically splaying picker finger 10 can only be disengaged from adata cartridge 22 when the cartridge 22 is fully ejected from the pickerassembly 19 into a magazine 24, simplifying error recovery.

In another embodiment, the data storage system 120 may comprise amodular data storage system as shown and described in U.S. patentapplication Ser. No. 09/137,350 referred to above. Referring nowprimarily to FIG. 9, the frame assembly 128 comprises a lower and upperplate 164 and 165, around which a U-shaped guide track 130 and U-shapedgear rack 162 are located. A picker 119 may be positioned along theU-shaped guide track 130 as described above with respect to otherembodiments. The frame assembly 128 may be moved along a Z axis by avertical lift system 167, allowing the data storage system 120 to accesscartridge receiving devices such as storage magazines 124 and cartridgeread/write devices 126 which have been stacked vertically in multiplelayers (not shown) along a Z axis.

The vertical lift system 167 may comprise a pinion gear assembly 169mounted on the upper plage 165. The vertical lift system 167 may furthercomprise an actuator system 171 operatively associated with the piniongear assembly 169 for vertically translating the frame 128 among thelayers of cartridge receiving devices 124 and 126.

The pinion gear assembly 169 may comprise a first pinon gear 173 and asecond pinion gear 175, mounted diagonally opposite one another as shownin FIG. 9. First and second gear racks 177, 179 are mounted to the frame128, mounted diagonally opposite one another in alignment with thepinion gears 173, 175. Each pinion gear 173, 175 engages with the firstand second gear rack 177, 179 respectively. The actuator system 171 ispreferably comprised of a motor 181 and a gear/shaft assembly 183 tooperably connect the motor 181 to the pinion gears 173, 175. As themotor 181 turns the pinion gears 173, 175, the frame 128 and the picker119 are moved along a Z axis, providing access to the multiple layers ofcartridge receiving devices 124, 126.

Referring now to FIGS. 9, 10 a, and 10 b, the cartridge picker assembly119 in this embodiment may be moved either laterally or vertically alonga Z axis to disengage the automatically splaying picker finger 110 froma data cartridge 122.

After the thumb assembly 121 is engaged with a data cartridge 122 it maybe moved along a first displacement path in direction 139 into aretracted position, thereby pulling the data cartridge 122 into thecartridge picker assembly 119. To disengage the automatically splayingpicker finger 110 from the data cartridge 122 in a magazine 124, thecartridge 122 is first moved to the magazine 124 and inserted. Toposition the cartridge 122 adjacent the magazine 124, the cartridgepicker assembly 119 is first moved along a second displacement path bothlaterally by the picker positioning system (e.g., 34) and vertically bythe vertical lift system 167 until the cartridge 122 is properlypositioned. The second displacement path traveled by the cartridgepicker assembly 119 is substantially perpendicular to the firstdisplacement path of the thumb assembly 121, as discussed above.

The thumb assembly 121 is then moved along the first displacement pathin direction 138 so that the body 186 of the thumb assembly 121 pushesthe data cartridge 122 into the magazine 124, as shown in FIG. 10a.

With the data cartridge 122 seated in the magazine 124 and the thumbassembly 121 still in the extended position, the cartridge pickerassembly 119 may be moved along the second displacement path todisengage the automatically splaying picker finger 110. In this example,the cartridge picker assembly 119 is moved down along a Z axis indirection 191 by the vertical lift system 167. As the cartridge pickerassembly 119 is moved down, the data cartridge 122 remains in themagazine 124 and the tip 114 of the automatically splaying picker finger110 is pulled out of the notch 123 in the side 125 of the data cartridge122. The automatically splaying picker finger 110 is pulled from thelocked position 141 to the retracted position 140 by the spring 117. Thethumb assembly 121 may then be moved along the first displacement pathinto the retracted position inside the cartridge picker assembly 119,and the cartridge picker assembly 119 may be moved to another datacartridge.

Referring now primarily to FIGS. 11a-11 f, the operation of theautomatically splaying picker finger 10 when engaging a cartridge 22 ina cartridge read/write device 26 will be discussed in more detail.

A data cartridge 22 may be fully engaged in the housing 50 of acartridge read/write device 26, as shown in FIG. 11a. In one preferredembodiment, the housing 50 is relatively longer than a cartridge storagemagazine 24, so that when a data cartridge 22 is fully inserted in theread/write device 26, the notch 23 in the cartridge 22 is covered by thehousing 50.

To engage the automatically splaying picker finger 10 with the datacartridge 22, the cartridge read/write device 26 first ejects thecartridge 22 to an ejected position 55, as shown in FIG. 11b, such thatthe notch 23 in the cartridge 22 is exposed. In one preferredembodiment, the ejected position 55 is about 12 mm from the fullyinserted position.

The thumb assembly 21 (see FIG. 11b) then moves toward the datacartridge 22 as described above with respect to FIGS. 7a-7 e and 8 a-8e, and the automatically splaying picker finger 10 moves into the lockedposition 41 with the tip 14 engaged in the notch 23. The thumb assembly21 and data cartridge 22 may then be retracted into the cartridge pickerassembly 19 to be transported to another cartridge receiving device 24or 26.

The thumb and finger assemblies 21 and 10 may also disengage from a datacartridge 22 after inserting the cartridge 22 into a cartridgeread/write device 26, as shown in FIGS. 11c and 11 d. The cartridgepicker assembly 19 carrying the data cartridge 22 is first positionedadjacent the cartridge read/write device 26 as described previously. Thethumb assembly 21 with the automatically splaying picker finger 10engaged to the data cartridge 22 is then moved out of the cartridgepicker assembly 19 in direction 38 toward the cartridge read/writedevice 26.

As the data cartridge 22 nears the fully inserted position, the face 16of the automatically splaying picker finger 10 contacts a bezel 48 onthe housing 50 of the cartridge read/write device 26. The angled face 16is thereby caused to pivot down into the splayed position 42,disengaging the tip 14 from the notch 23. The thumb assembly 21continues to push the data cartridge 22 into the cartridge read/writedevice 26 until it is fully inserted and the notch 23 is covered by thehousing 50. The thumb assembly 21 may then be retracted into thecartridge picker assembly 19 with the tip 14 of the automaticallysplaying picker finger 10 sliding along the edge 25 of the datacartridge 22.

Alternatively, the drive housing 50 of a cartridge read/write device 26may be formed without a bezel 48 and with a more shallow cartridgecavity such as the magazine 24 described above. In this case, engagementand disengagement of a data cartridge 22 in a cartridge read/writedevice 26 would operate in the same fashion as with respect to amagazine 24.

It is contemplated that the inventive concepts herein described may bevariously otherwise embodied and it is intended that the appended claimsbe construed to include alternative embodiments of the invention exceptinsofar as limited by the prior art.

What is claimed is:
 1. A cartridge picker for selectively engaging and disengaging a cartridge, comprising: a thumb assembly mounted to said cartridge picker so that said thumb assembly is moveable along a first displacement path between an extended position and a retracted position; a finger having a cartridge engagement end and a mounting end, the mounting end being mounted to said thumb assembly, said finger being moveable between a retracted position and a splayed position, so that moving said cartridge engagement end of said finger against a cartridge causes said finger to move into the splayed position; and a cartridge picker positioning system operatively associated with said cartridge picker, said cartridge picker positioning system moving said cartridge picker between a first position and a second position along a second displacement path that is substantially perpendicular to the first displacement path so that said finger disengages the cartridge when said thumb assembly is in the extended position and when the cartridge picker is moved to the second position.
 2. The cartridge picker of claim 1, wherein said finger is aligned with the cartridge when said cartridge picker is located in the first position.
 3. The cartridge picker of claim 2, wherein said finger is not aligned with the cartridge when said cartridge picker is located in the second position, so that said finger is located alongside the cartridge when said thumb assembly is in the extended position and the cartridge picker is in the second position.
 4. The cartridge picker of claim 1, wherein said finger is pivotally mounted to said thumb assembly.
 5. The cartridge picker of claim 1, wherein said finger comprises a hooked tip at the cartridge engagement end.
 6. The cartridge picker of claim 1, further comprising a spring attached between said thumb assembly and said finger so that said finger is pulled toward the retracted position.
 7. The cartridge picker of claim 1, wherein the mounting end of said finger is higher along a Z axis than the cartridge engagement end of said finger.
 8. The cartridge picker of claim 7, wherein the mounting end of said finger is between about 10 mm and about 20 mm higher along a Z axis than the cartridge engagement end of said finger.
 9. The cartridge picker of claim 1, wherein the first position is between about 6 mm and about 8 mm from the second position along the second displacement path.
 10. The cartridge picker of claim 1, wherein the cartridge engagement end of said finger comprises an angled face.
 11. The cartridge picker of claim 10, wherein the angled face of said finger is angled between about 12 degrees and about 20 degrees from a Z axis.
 12. A cartridge picker for selectively engaging and disengaging a cartridge, comprising: a thumb assembly mounted to said cartridge picker so that said thumb assembly is moveable along a horizontal displacement path between an extended position and a retracted position; a finger having a cartridge engagement end and a mounting end, the mounting end being mounted to said thumb assembly, said finger being moveable between a retracted position and a splayed position, so that moving said cartridge engagement end of said finger against a cartridge causes said finger to move into the splayed position; and a cartridge picker positioning system operatively associated with said cartridge picker, said cartridge picker positioning system moving said cartridge picker between a first vertical position and a second vertical position along a vertical displacement path so that said finger disengages the cartridge when said thumb assembly is in the extended position and when the cartridge picker is moved to the second vertical position.
 13. The cartridge picker of claim 12, wherein said finger is aligned with the cartridge when said cartridge picker is located in the first vertical position and said finger is not aligned when said cartridge picker is located in the second vertical position, so that said finger is located under the cartridge when said thumb assembly is in the extended position and the cartridge picker is in the second vertical position.
 14. A method for engaging a data cartridge with a cartridge picker, comprising: providing a cartridge picker comprising a thumb assembly moveable along a displacement path between an extended position and a retracted position and a finger mounted to the thumb assembly so that the finger may be moved between a retracted position and a splayed position; positioning the cartridge picker adjacent the data cartridge; moving the thumb assembly along the displacement path toward the cartridge, causing the finger to move to the splayed position by pressing the finger against the data cartridge; and continuing to move the thumb assembly along the displacement path toward the cartridge until the finger engages a notch in the cartridge. 